The Winter Jazzfest turned nine this year, and it’s matured into a known quantity, a New York cultural landmark. Its variety of routines have worn in enough to develop some comforting predictability. For such a scrappy, low-to-the-ground happening designed around emerging artists and new repertoires, that’s an achievement.

My experience began a little after 6:15 p.m. on Friday night with a half-set from Maria Neckam, a vocalist whose compositions are informed by unconventional phrasing and a striving for serenity. It ended with a foreign folk song, wrapped in warm flourishes, by bass clarinetist Oran Etkin, sometime after 2:30 a.m. on Sunday morning. In between I saw everything between international headliners and relative unknowns, intricately-plotted compositions and completely free improvisation, high-concept one-offs and bands shaped over decades. At Winter Jazzfest, you expect the entire gamut.

If you see a significant part of the two-night, 73-band marathon, you will marvel at the incredible diversity of inspiration, often from musicians you haven’t heard of, reflecting just about every sonic impulse and genre-hybrid imaginable. You may later wonder if this coalition of disparate ideas can cohere without a central core aesthetic, or what that core might be in 25 years, but it won’t matter at the time.

Pleasingly, there will be more excited young people — musicians, culture hounds, couples on dates — than you normally see at jazz shows. Less pleasingly, prohibitively large crowds, even in cold rain, will prevent all but concertgoing ninjas from getting into everything they set out to attend.

You will hear some things that resonate with you. You will hear other things that feel too noisy, too smarmy, too complex; that will be OK because you will simply get up and move to another venue. You will stand in line outside the Zinc Bar. You will still wonder how so much talent could amass in one place, even in a city as enormous as New York. You will, if you pursue it any further, realize that even these dozens of bands collectively represent only the tip of the iceberg.

Many of the bands feel like all-in experiments in the unusual. Such ambition makes sense if you know the event’s origins — and continuing function — as a showcase for venue bookers and concert presenters. I appreciated this in theory, if not always in practice. I saw a tribute to the eclectic film composer, performer and producer Ryuichi Sakamoto, brought together by violinist Meg Okura; soon afterward, I checked out harpist Brandee Younger’s rescoring of fellow harpist Dorothy Ashby‘s cult classic album Afro-Harping, featuring a live DJ. Later that night, pianist Dan Tepfer and alto saxophone legend Lee Konitz were joined by the Harlem String Quartet, which interpreted Tepfer’s live compositions (he used a MIDI keyboard to beam information to the quartet’s iPhones). It was also the evening I saw Corey King’s TAFFY, where the front line included both King’s trombone and Max Siegel’s bass trombone, and the CHURCH project led by Mark de Clive-Lowe, whose violent rhythm section of Mark Kelley (bass) and Nate Smith (drums) adjusted to his impulses on piano, keyboard and drum machine.

My favorite of the go-for-broke bands — also, somehow, on Friday night — was the trombone choir headed by Jacob Garchik. There’s a backstory as to why he calls his band an atheist gospel trombone choir, and on his 2012 album The Heavens, he overdubs himself on all the parts. But all you really need to know is that in concert, he marshals seven trombones, tuba and drums. There was joy and melancholy alike.

For all the bands that you would use the term “project” to describe, there are always a few bookings at Winter Jazzfest that feel a bit like coronations, or confirmations of greatness. On Saturday night at the largest venue, Le Poisson Rouge, the veterans known as The Cookers (with Victor Lewis subbing in on drums) delivered what felt like a keynote address with the oomph and roar of a bygone era. They were followed by alto saxophonist Rudresh Mahanthappa, whose new guitarist David Fiuczynski presented a flashy and fusion-y foil to his swirling tessellations. And after Mahanthappa’s set, fellow saxophonist James Carter, playing with his organ trio, was his usual colossal self, entertaining by destroying.

There’s always regret that you didn’t see more. I missed it, but there was buzz from both the jazz neophytes and the indoctrinated around the trio of Eric Revis (bass), Kris Davis (piano) and Andrew Cyrille (drums). There were lines spilling into the theater lobby, and out the door to get into the theater lobby, for the beloved band Kneebody and for the quartet led by drummer Nasheet Waits, featuring pianist Vijay Iyer. Apparently Jason Lindner’s Breeding Ground, an 11-piece expansion of his Now vs. Now power-groove trio, stood out. I couldn’t say — I got crowded out of that one too.

For me, that meant checking out the labyrinthine compositions of Michael Formanek’s Cheating Heart quartet; the loose structures and audibles of bassist Mario Pavone’s trio (with Dave Ballou on trumpet and Tyshawn Sorey on drums); the slow-cooked, bitter-herb art-songs in Korean and English [of] Sunny Kim; the elusive trio of Tony Malaby, which used Dan Peck’s tuba as a 360-degree pivot; the proggy kitchen sink of guitarist Rafiq Bhatia’s quartet; a remarkable sequence of funk-rock tunes from drummer Ari Hoenig’s quartet — one melody was “Oops, I Did It Again” — which featured saxophonist Tivon Pennicott’s remarkable intuition for phrasing; the sprawling AfroHORN ensemble, which sounded like an Afro-Cuban ritual gathering from a fitful dream; the group Merger, where Ornette-Coleman-ish melodies gave way to the improvisatory id of trumpeter Kurt Knuffke and reedman Andrew D’Angelo.

Overall, I heard more guest spots from rappers than standards, more boom-boom-chik than ding-ding-a-ling, more outsider lexicography than established languages. Maybe that’s why some of my standout sets tasted of the familiar. Brian Carpenter’s Ghost Train Orchestra, which specializes in tightly-arranged music of the 1920s and ’30s, snuck its way to my top ten list in 2011. Live, the nine-piece band was a reminder of how wild and carnivalesque that old-time music really was, and how satisfying the swing impulse remains amid all the wheel reinvention.

And then there was The Fringe, the group of three Boston-based Berklee professors who meet weekly to make something out of nothing. On the burners, saxophonist George Garzone had a packed, sitting-on-the-aisle-steps theater shouting encouragement with his every move — that wasn’t new. But when he initiated a ballad, over 200 people sat at the edges of their seats in rapt silence. It was devastating, all the more so for being something I’ve never witnessed at Winter Jazzfest, which many treat as much as a gabby family reunion as an art-music exhibition.

When Winter Jazzfest turns 10, we’ll have come to expect the crowds, the wild ambition, the information overload. We’ll be ready for the crazy. Luckily, we still won’t be prepared for the surprises.